Professor Hall moved to Australia from England four years ago, and, as he wandered the streets of Brisbane’s suburbs, he was struck by the lack of backyards.

“I’d never seen this before,” Professor Hall told AAP from his office at Queensland’s Griffith University. “It reflected changes in lifestyle in Australia for the worse.”

In developing, outer suburbs across the country, home buyers are purchasing blocks of land to build their own home, he said. They are encouraged by builders to construct the biggest house then can fit on the lot and the “backyard is not seen as very interesting”. It is in the builder’s interest to sell floor space, Prof Hall said.

“New names are invented to cover all these rooms that you now have but don’t really have any function (like) activity rooms,” he said. “You find that the situation is quite dramatic. Any aerial photos you find, it really stands out, you get the older suburbs – they’re covered by trees and the newer ones are all just roof-to-roof.”

Professor Hall wrote a report about his findings for Griffith University’s Urban Research Program, titled Where Have All the Gardens Gone? An Investigation into the Disappearance of Backyards in the Newer Australian Suburb.

He said the trend took hold in the mid-1990s, coinciding with longer working hours.

“People in Australia are now working very long hours (particularly) people in the outer suburbs … (people are) working over 50 hours a week, working weekends, not taking their holidays,” he said. “People often don’t notice the lack of outlook because they’re not there in the daytime. The house is designed as a supposed investment but you can’t enjoy it.”

Shrinking backyards are forcing people indoors, causing a shift in leisure activities and lifestyle choices, he said.

“It’s completely contrary to these stories of real Australia because we’re still maintaining the story of the laid-back, outdoor, casual lifestyle when in fact the reality is moving rapidly in the opposite direction.”

Backyard lovers such as kids and retirees who like “pottering in the garden” are suffering most from the shrinkage, Prof Hall said.

“Children now sit in their bedroom and play computer games. Generations of children have grown up without any contact with the natural world.”

There is also an environmental impact.

“There’s a huge ecological function of the planted areas around the house,” Prof Hall said.

This has an impact particularly in the Australian climate. Big, shady trees are replaced with energy guzzling air-conditioning and rain that would nourish the garden is flushed down the stormwater drain.

Prof Hall said front yards don’t offer the security and privacy of a backyard and for maximum pleasure a backyard should reach at least 100 square metres, though design is more important.

“What is worrying is that the older suburb house with a big backyard is no longer being built in Australia,” he said. “What is the quality of life in these places? It’s quite frightening really.”